The Cannabis Terpenes – What are they and what difference do they make?

Terpenes are a class of natural products comprising over 30,000 compounds.  Terpenes play an important role in a wide range of biological functions and interactions, including:

• Defence against insects and animals
• Resistance to Microbial Diseases
• Resistance to Viral Diseases
• Communications to attract beneficial insects and animals
• Cell growth modulation 
• Photoprotection
• Cross Membrane Transportation
• Fluid control
• Plus many more…

The terpenes found in cannabis, combined with the cannabinoid acids, provide these same functions for the cannabis plant; and features that make them biochemically important for the plant are the features that make terpenes important compounds from our perspective, and arguably just as important as the cannabinoids, in terms of both the recreational and therapeutic consumption of cannabis products.  

For recreational consumption of cannabis, the importance of the terpenoid profile cannot be overstated.  Not only do the terpenes add ‘flavour’ to the experience, but they contribute dramatically to the psychoactive effects of the cannabinoids and the terpenes are responsible for the secondary effects, such as the difference between ‘traditional sativa’ and a ‘traditional indica’.  Looking past the psychoactivity of the cannabinoids to their other potential benefits and it makes sense that the terpenes should have a significant impact on other benefits associated with cannabis.

The therapeutic properties of terpenes are extensive, and they are at the root of many traditional medicines.  The following table shows some selected terpenes and their known therapeutic properties:

Therapeutic Properties	Terpene
Anti-inflammatory	Myrcene, humulene, eucalyptol, and many others
Pain relief	b-caryophyllene, a-bisabolol, a-phellandrene…
Memory retention	d-3 carene, a-pinene, b-pinene, p-cymene…
Anti fungal	Camphene, terpinolene, geraniol
Anti viral	Eugenol, ocimene
Anti bacterial	Phytol, humulene, farnesene
Drying agent	d-3 carene

The chemistry of terpenes:

Terpenes are made up of 5-carbon building blocks.  Monoterpenes are C-10 (2 units), sesquiterpenes are c-15 (3 units), and diterpenes are C-20 (4 units).  Terpenes are also the building blocks for other natural products such as steroids.  

We are very familiar with monoterpenes as they are the main constituents in essential oils and essential oils have been an integral part of traditional medicines dating back thousands of years.  Terpenes are one of several groups of natural compounds that have formed the mainstay of traditional medicines.  The reason is these compounds are bioactive and serve a purpose, which for the plants that make them, is often associated with defence and communications.  In the case of the cannabis plant, it has gone further and uses both terpenes and cannabinoids in abundance to achieve its purposes.

So, if we are serious about our cannabinoids, we should be serious about our terpenes too.  The challenge is that there are so many, even in the cannabis plant alone.  We can; however, make some sense of them by grouping them.

Monoterpenes 

“Aliphatic monoterpenes” can be described as the basic terpenes; they are simple unsaturated hydrocarbons, and they have the formula C10H16.  Because there are many ways to put 10 carbon atoms together, there is an interesting range of terpenes in this group and a lot of them are familiar.  Of these, a-pinene, b-pinene, b-myrcene, a-phellandrene, terpinene, ocimene, limonene, sabinene and 3 carene are common in most strains of cannabis.  Other aliphatic terpenes that are of interest but typically found elsewhere include camphene.  Note the ‘ene’ at the end means unsaturated hydrocarbon.

Each of these terpenes has its own unique set of properties; however, as a group they are all good solvents and their use ranges from industrial cleaning to electronics and manufacturing.  Their solvent-like properties also make aliphatic terpenes useful in other areas because they aid in transdermal transportation of active compounds, and they are also able to cross the blood brain barrier, both of which are interesting features when we start looking at their pharmacology. They are also known to be good anti-bacterial and anti-viral compounds, and this may be a large part of their function in the plant kingdom.

“Monoterpenoids” can be describes as the group of terpenes that contain additional functional groups, usually containing an oxygen atom, and these can be further grouped into alcohols, aldehydes and ketones.

Monoterpene Alcohols include Linalool, geraniol, phytol, nerolidol, bisabolol, borneol, terpineol, 1,8-cineole (eucalyptol), terpinene-4-ol, menthol, and carvacrol.  Note the “ol” at the end means alcohol.  These terpenes are typically present in lesser quantities that the aliphatic terpenes; however, they bring a range of additional features.

Monoterpene aldehydes include citral, etc.  Note the “al” at the end means aldehyde.

Monoterpene /ketones include fenchone, pulegone, thujone, etc.  Note the “one” at the end means ketone.

    Para-cymene is a unique compound and is often included as a terpene; however, it is actually an aromatic compound and has quite distinct and unique chemistry that distinguishes it from the monoterpenes.

Sesquiterpenes 

Sesquiterpenes are widely occurring and extensively studies natural products which, like their smaller monoterpene analogues, can be grouped into aliphatic hydrocarbons, alcohols, aldehydes and ketones, and higher oxygenates. 

    Aliphatic sesquiterpenes have a C15 structure and include farnesene, caryophyllene, humulene,  and germacrene D.

Sesquiterpene alcohols include farnesol, nerolidol, and guaiol. 

Sesquiterpene aldehydes include caryophyllene oxide.

These metabolites display a broad range of physiological properties, including antibiotic, antitumor, antiviral, cytotoxic, immunosuppressive, phytotoxic, antifungal, insect antifeedant, and hormonal activities.

Diterpenes

    Aliphatic diterpenes have a C20 structure and like monoterpenes and sesquiterpenes can be grouped into aliphatic, alcohols, aldehydes and ketones, as well as higher oxygenates.  At this point the complexity of what is out there is enormous.

Details on Important Terpenes – Cool Stuff on Some Cool Compounds

Myrcene 

• Myrcene is the most prevalent terpene in cannabis and can be up to 50% of the total terpenes in cannabis.
• Myrcene is also found in juniper, hops, and mangos.
• Myrcene is believed to contribute significantly to the effects of cannabinoids
• Myrcene has a citrus-woody aroma that can be a bit spicy or peppery, and it gets its name from Myrcia sphaerocarpa, a plant native to Brazil that has been used medicinally for hundreds of years.
• Myrcene has been used in traditional medicines to treat discomfort related to hypertension, dysentery, diarrhea, and diabetes. 
• Myrcene has shown antibiotic, antimutagenic, analgesic, anti-inflammatory and sedative properties.
• Myrcene can change the permeability of cell membranes, modifying the ability to absorb cannabinoids and other active ingredients.
• Myrcene is thought to be the major contributor to the distinctions between indica and sativa strains with higher concentrations of myrcene contributing to the couch-lock effect typical of the indica strains.
• Myrcene is an antioxidant and may protect against peroxides and UV light.
• Myrcene has shown anti-tumor behavior in some studies

Limonene

• Limonene is the second most prevalent terpene in cannabis
• Limonene has a recognizable zesty citrus fragrance typical of lemon but also in oranges, limes and grapefruit.
• Limonene has a broad range of uses in industry such as cleaning, perfumes, personal care products and medicines.
• One of the most studied terpenes, limonene has been established as an antimicrobial, antibacterial, antioxidant, and anti-inflammatory agent, and potentially contains numerous other health benefits.
• Limonene has been studies for a range of benefits including weight loss, an aid in digestion, preventing gastric stress, treating bronchitis, heartburn and gallstones.  

Alpha-pinene

• α-pinene is the primary terpene found in pine trees which gives them their characteristic “piney fresh” scent. α-pinene is the most familiar and commonly found terpene in nature and is found in pine and conifer trees, rosemary, and orange peels, β-pinene is responsible for the more earthy aromas such as those found in basil, dill, parsley, and hops. 
• Alpha-pinene (α-pinene) is one of the most notable and familiar terpenes and it is used in ordinary household products and cleaners.
• Because α-pinene can cross the blood-brain barrier -– the mechanism that protects the brain from most substances that disturb neural function and brain composition -– α-pinene has been found to improve cognitive function and memory, increase focus and alertness, and reduce anxiety. It also has many promising uses in patients with Alzheimer’s and other neurodegenerative disease (Parkinson’s disease, Huntington’s disease, multiple sclerosis, etc.). 
• α-pinene has also been shown to manage pain, act as a systematic anti-inflammatory, fight cancer cells while slowing the growth of human cancer, combat bacteria and infection, work as an antioxidant, and open the airways in the lungs for people with asthma (as an alternative to a steroid inhaler). 

Ocimene

• As an acyclic terpene (similar to myrcene), 
• Ocimene has a sweet, citrusy, herbaceous, and woody odor. 
• Ocimene is found in mint, parsley, tarragon, pepper, basil, mangoes, kumquats, orchids, and cannabis. It is used in perfumery for its sweet herbal scent. 
• Ocimene has been found to possess antifungal and anti-inflammatory properties.

a-phellandrene

• α-Phellandrene gets its name from Eucalyptus phellandra (now called Eucalyptus radiata) from which it can be isolated. 
• α-Phellandrene has been found to reduce pain sensitivity and increase energy levels
• α-Phellandrene contains potential anti-cancer properties.
• α-Phellandrene is easily absorbed, making it a common additive in cosmetic products and fragrances because of it’s pleasant aromas.
• α-Phellandrene has been a staple in holistic Eastern medicine for a long time, used for its antifungal and antibacterial properties.

a-terpinene

• Alpha terpinene (α-terpinene) is one of three monoterpenes known as terpinene, along with beta-terpinene and gamma-terpinene. α-terpinene occurs naturally in many varieties of plants, including allspice, eucalyptus, citrus, juniper, cardamom,  marjoram, and cannabis. 
• Known for its smoky, woody scent, α-terpinene is a colorless liquid that is most commonly utilized by adding more pleasant scents into industrial fluids. It is also used in the beauty and pharmaceutical industries as a flavor and aroma additive. In biology, it is known as both a component of volatile oil and as a plant metabolite.
• α-terpinene possesses strong antioxidant properties and has also been researched as a potential cancer treatment. Recent studies have shown α-terpinene contributed to the inhibition of breast cancer cell growth.
• α-terpinene is a major constituent of Tea Tree Oil.

b-pinene

• β-pinene is most known for it’s a woody and piney smell. 
• Because both β and α-pinene share the same plant sources, they also share similar therapeutic qualities and characteristics. The main differentiator between these two terpenes is their smell. Whereas α-pinene possesses the unmistakable fresh and earthy scent (think pine and rosemary), β-pinene has a fresh, woody, and spicy aromatic quality (think dill, parsley, basil or hops). 
• β-pinene is commonly used in fragrance, essential oils, cooking as a flavoring additive and it also can serve as a preservative. 
• Both α-pinene and β-pinene are noted for their ability to increase mental alertness, clarity, and overall cognitive functions. 
• They also have been researched for their significant applications in bronchodilation, pain relief, epilepsy and cancer treatment, and neuroprotection. The pinenes are also widely recognized as an anti-inflammatory, antidepressant, (targeted at treating conditions such as arthritis and fibromyalgia), antiseptic, and antioxidant. 

Camphene

• has a pungent camphor-like odor. It is found in low concentrations in many essential oils such as cypress, nutmeg, rosemary, camphor, neroli, ginger, and valerian.
• Camphene has been present in daily life since the mid-19th century, as it was used as fuel for lamps. Today, camphene is widely used in perfumes for its woody, piney scent, and as a flavor additive for food.
• Because of camphene’s known ability to potentially target skin conditions like psoriasis and eczema, it is often used in cannabis salves and topicals. Other studies promote camphene as a potential anti-fungal and antibacterial agent.  Camphene has also shown promise as a strong anti-inflammatory and pain reliever. 

Delta 3 Carene

• Carene occurs naturally as a component of turpentine, with content as high as 40% depending on the source. It is also found in rosemary, basil, pepper, cedar, and cannabis. Carene has a sweet and woodsy odor, sometimes with a subtle hint of lemon.
• Carene is found in many essential oils used in aromatherapy. It is also used in cosmetics, perfumes, and foods as a flavoring agent. 
• Carene has been studied for its potential anti-inflammatory properties, specifically in the reduction of edema.  It also appears to increase the incorporation of calcium into bones (mineralization), improving overall bone health. These bone-strengthening properties make carene a potential treatment for osteoporosis. 

Linalool

• Linalool is one of the most recognizable aromas of all the terpenes.¹ Linalool is a common terpene found in cannabis but is also naturally occurring in many flowers and spice plants. 
• Over 200 species of plants produce linalool, but it’s best known for giving lavender its distinctive flavor and aroma. 
• Linalool is found mainly in the families Lamiaceae (mint and other herbs), Lauraceae (laurels, cinnamon, rosewood), and Rutaceae (citrus fruits), but also birch trees and other plants from tropical to boreal climate zones.² It’s even been found in some fungi.
• A natural relaxant, linalool is often used in aromatherapy as a sleep aid and has been utilized as a treatment for anxiety for thousands of years. 
• Linalool exhibits calming and sedative effects when inhaled, along with lower aggression and higher social engagement. 
• Linalool has been linked to a variety of health benefits³ including analgesic, anxiolytic, sedative, anti-inflammatory, anti-tumor, and antibacterial effects.
• Linalool makes up a significant portion of lavender essential oil, which has reported anti-agitation and antidepressant effects,⁴ most likely due to its activity on the NMDA receptor. Linalool is also crucial in the production of Vitamin E in the body.
• Linalool is used as a scent in up to 80% of perfumed hygiene products and cleaning agents, including soaps, detergents, shampoos, and lotions. 

Borneol

• Borneol is one of the most popular terpenes used in the perfume industry due to its cool, minty, and spicy scent. 
• Borneol has a history of use in a range of healing capacities.
• Borneol is found in a multitude of plants including ginger, thyme, rosemary, sage, marjoram, cardamom, cinnamon, mint, nutmeg, sagebrush, tarragon, turmeric, wormwood, mugwort, sunflowers, artemisia, and cannabis. 
• Borneol has been used in Chinese medicine for nearly 2500 years to treat chronic and acute pain as what is known as “moxa,” which is compounded from mugwort.
• Modern science continues to confirm that this terpene has powerful healing applications such as the systemic and topical use treat pain without drowsiness, unlike many western pain relief medications. 
• Borneol also has significant medicinal and therapeutic implications in cancer treatment, as an anti-inflammatory, cardiovascular treatment (anti-coagulant), antioxidant, neuroprotective (potential prevention and treatment of Alzheimer’s Disease), antiseptic, bronchodilation, gingivitis treatment, and digestive tract facilitator. Borneol also has therapeutic applications in the treatment of anxiety, mental clarity and energy, memory retention, and overall wellness. 
• What’s more, borneol has been found to have compound “synergistic effects” when combined with other terpenes, cannabinoids, and medications because it lowers the blood-brain barrier which allows greater absorption of other medicines a patient might receive. 

a-terpineol

• α-terpineol is a terpene alcohol found in a variety of plants including lilac trees, pine trees, lime blossoms, clary sage, coriander, lemon, star anise, mandarin orange, rosemary, lavender, juniper, eucalyptus, and cannabis.
• α-terpineol is a critical component of tea tree oil.
• α-terpineol has a pleasant aroma often compared to lilac and sometimes described as ‘forest-like.’ It is found in many household and personal products such as soaps, candles, perfumes, and lotions. It is also used in food for flavor in confections, beverages, and condiments.
• Many studies support significant evidence towards α-terpineol’s antioxidant, anti-inflammatory, antibacterial, anticonvulsant, anti-microbial, anti-fungal, anti-proliferative, and anti-cancerous properties. Some studies also indicate that α-terpineol is an immune system stimulant, and when used in aromatherapy, it has been reported to clear the sinuses and shorten the life of the common cold. When used in combination with topical therapies, α-terpineol may enhance the permeability and effectiveness of a lipid-soluble solution. 
• α-terpineol is found in a wide variety of cannabis plants, and many consumers will recognize its piney scent in many popular strains. 

Eucalyptol

• Eucalyptol is also commonly known as cineole. Eucalyptol not surprisingly got its name from eucalyptus, of which it’s the primary terpene. Eucalyptol comprises over 80% of the total in the essential oils from eucalyptus trees, and it’s also found in tea tree, mugwort, bay leaves, sweet basil, rosemary, sage, and cannabis. 
• Eucalyptol is utilized as an ingredient in many products you associate with minty-freshness, including mouthwash, toothpaste, and cough suppressants. It is also prominent in the wellness industry for its use in aromatherapy, massage lotions, and oils.
• Eucalyptol is known for possessing pain-relieving, anti-inflammatory, and antioxidant properties, and is an effective treatment for nonturbulent rhinosinusitis. Eucalyptol’s anti-inflammatory cytokine inhibition has been shown to control airway mucus hypersecretion and asthma. Eucalyptol has also been shown to suppress colorectal cancer cell growth in humans. 

Geraniol

• Geraniol is the primary element of rose oil, palmarosa oil, and citronella oil. It also occurs in small quantities in geranium, lemon, and many other essential oils.
• Geraniol has a rose-like scent and is commonly used in the cosmetics industry for lotions, perfumes, soaps, and detergents. It is also used to flavor sweet foods like ice cream and candy. 
• Research has shown geraniol to be an effective plant-based mosquito repellent. 
• Geraniol has the unique ability to attract bees.  Geraniol is produced by the honey bees’ scent glands to mark nectar-bearing flowers and to mark the entrances to their hives. 
• Geraniol has been studied for its antimicrobial, antibacterial, and pain-relieving properties. 
• Geraniol has strong antioxidant properties which may be promising potential in cancer research. 
• Geraniol functions as a neuroprotectant, which could be utilized in the treatment of diabetes.
• Geraniol, like a number of other terpenes, enhance the skin’s ability to absorb active ingredients like cannabinoids. 

Beta-caryophyllene

• ß-caryophyllene’s distinctive flavor and aroma contributes to the spiciness of black pepper and is also abundant in basil, copaiba, black caraway, oregano, lavender, allspice, fig, roman chamomile, cloves, hops, cinnamon, ylang-ylang, and rosemary.
• ß-caryophyllene’s is one of the few terpenes that the FDA recognizes as “safe” to consume in large doses. 
• ß-caryophyllene is unique in that it appears to interact with the endocannabinoid system in a manner like CBD.
• ß-caryophyllene is widely recognized for its use in both acute and debilitating states of pain relief, but also has applications for immune system enhancement, stress and anxiety reduction, and anti-inflammation. It also has been found to promote healthy gut and digestion by protecting the cells that line the digestive tract.

Humulene 

• Humulene gets its name from Humulus lupulus (common hops) and is one of the predominant terpenes found in this popular plant. Humulene is also commonly called α-humulene. While humulene is closely related to β-caryophyllene, it is a different isomer with distinct properties, and it has yet to be recognized as a dietary cannabinoid.
• In addition to hops, humulene is also found in cannabis, basil, clove, black pepper, sage, and ginseng. Like myrcene and pinene, humulene is a fundamental element in the overall aromatic profile of cannabis. This is likely because humulene is produced in the resin of mature cannabis plants to help form a natural defense system, fighting against pests, animals, and bacteria.
• Humulene has shown to be a powerful anti-inflammatory and analgesic. It also displays tumor-fighting and anti-cancer properties when combined with phytocannabinoids and other terpenes. 
• Humulene is unique because, like THCv, it acts as an appetite suppressant, making it promising for weight loss treatments. 

Bisabolol

• Bisabolol, also known as levomenol, is recognizable for its sweet and light floral aroma.
• Bisabolol has been used in the production of cosmetics, perfumery, and skincare products for hundreds of years. This is likely both due to its calming properties and subtle, pleasing aroma.
• Bisabolol has been researched for its anti-inflammatory, anti-microbial, and analgesic properties.  
• Bisabolol also has been studied for its ability to inhibit the growth of cancer cells.